Abstract

The deaths related to riding roller coaster are insignificant, but there are multiple reports about nonfatal injuries like neurological, cardiovascular, urological, ophthalmological and connective tissue injuries. The most common lesions reported in the literature associated with riding roller coaster are cardiac and brain damage. We conducted a literature review from 1995 to 2017 using the keywords roller coaster and neurological/vascular injuries. We found 21 articles related to neurological injuries and 13 for vascular injuries it was important for the selection that articles clearly describe neurological o vascular clinical cases and the association with riding a roller coaster. Finally, we work only with 9 articles for neurological and 6 for vascular injuries. Some of the cases presented in this review were correlated to pre-existing trauma or aneurysms. With this review is clear that the risk of injury by riding a roller coaster is low, but emergency physicians should know that amusement park rides could be related to inexplicable symptoms associated with extreme conditions in the roller coaster rides.

Keywords

Roller coaster; Neurological injury; Vascular
injury

Introduction

The country with the larger number of roller coaster is the
United States and there is no real control over the accidents
related to riding a roller coaster, it is mentioned that in 2003
the US consumer Product Safety commission (CPSC) estimates
that 6900 non-occupational injuries attended in emergency
occurred on amusement rides [1]. The number of deaths
related to riding a roller coaster is insignificant 4 deaths
annually, compared with the nearly 300 million people each
year, but it is very important to take into account that there
are multiple reports about non-fatal injuries like neurological,
cardiovascular, urological, ophthalmological and connective
tissue injuries associated with riding roller coaster [2].

During riding roller coaster passengers are submitted to a
high speed, sharp curves and vertical and horizontal gravitational force (G force), a directionless quantity of linear
acceleration, which are usually dangerous for passengers, as
they cause changes in blood pressure and moving the blood
toward the feet or the head, these sudden acceleration
changes have been associated to risk of damage in different
organs or systems.

Whitcomb et al., recognized that cardiac and brain damage
as the most common causes of death following the roller
coaster rides [3]. The most powerful roller coasters are 4-6 G
forces, studies in pilots shows that 5-9 G forces are the
maximum limit for humans, but it is simplistic to do the
analysis based only on the G force without taking into account
other factors such as time, roller coaster applies brief
accelerations in different directions throughout the ride [4].
The injuries in the roller coasters are produced not only by the
acceleration (G force) also the velocity and ride time.

A series of medical case reports have described a potential
causal relationship between injuries and riding ‘high G force’
roller coasters [5,6].

Concerning to brain injury and roller coaster two
independent scientific panels and an engineering consulting
firm failed to find a connection [7,8].

An important limitation in assessing the cause of injury
during riding roller coaster is the unknown presence of preexisting
conditions that could augment a person’s
susceptibility to injury. There are also reports that suggest that
the neurological injury is most common among elderly persons
or in those with malformations or anticoagulant medication.

Literature Review

A literature search was conducted from 1995 to 2017 using
the keywords roller coaster and neurological/vascular injuries.
A combination of these keywords was used in subject headings
including the advanced search criteria, with the filter of years,
case reports in humans and full text articles.

The main goal was to identify case reports and relevant
studies describing injuries which clearly describe the relation
to the roller coaster ride.

The search of the data bases yielded 21 articles of
Neurological injuries and 13 of vascular injuries (Figure 1). 9
articles of neurological injuries and 6 of vascular injuries were
retained for full review. We eliminate studies if the case was
not well described or if the case was not clearly correlated to
the rollers coaster ride.

Figure 1: The number of articles that the different pages retrieve.

Excluded for the following reasons:

1. They were not case reports.

2. The relationship with the roller coaster and the ride was
not clear.

3. The information was not complete.

Results and Discussion

Neurological injuries

Neurological injuries associated with Roller coaster are very
infrequent [9] nevertheless; they represent a high percentage
among the roller coaster associated injuries.

Neurological injury is a term to encompass a big group of
injuries. Nevertheless, they differ in signs and symptoms, thus
the treatment must be accurate for the injury.

Most authors reported that the symptoms associated with
these injuries are commonly presented days after the ride, but
there are also reports of cases in which the symptoms are
present immediately after the ride, the most common
symptom is pain.

Some authors have reported neurological injuries in patients
that have been on a roller coaster with 3.5 G (meaning the
acceleration of the roller coaster was 3.5 times the gravity
acceleration) [10], which is relatively low in comparison with
other roller coasters.

On the next table, we resumed some cases with
neurological or ophthalmological injuries after a roller coaster
ride reported in medical literature (Table 1).

Table 1: An abstract of the articles selected associated with roller coasters and neurological and ophthalmological injuries.

The ophthalmic injuries presented symptoms immediately
after the ride and most of the neurologic injuries which start
their symptoms time after the ride.

The average age of the cases reported in Table 1 was 31, 25-
years-old. We analyzed if the gender was important in these
types of injuries and we didn´t find it relevant (41.66% women
vs. 58.33% men).

Vascular injuries

The vascular injuries are associated with the acceleration
and deceleration movements. Shearing tissues can be an
effect of moving a steady part from a fickle one.

In relation to pulmonary circulation, the main problem
associated with roller coaster is the sudden pressure changes
that can affect capillary circulation, resulting in ventilation
problems and capillary endothelial disruption.

In the Table 2, we resumed the cardiovascular and
pulmonary traumas share one fact in common: The onset of
the symptoms is immediately after the roller coaster and the
symptom and the most common is the pain, generally acute
pain.

Table 2: An abstract of the articles selected associated with roller coasters and vascular injuries.

Physiopathology of the injuries

Ventriculoperitoneal shunt malfunction: We review two
case reports of ventriculoperitoneal shunt malfunctions due to
a proximal catheter blockage related to roller coasters. In both
cases the shunt was occluded by normal tissue, coinciding with
the report of other authors [11-27]. In one case, the proximal
catheter was occluded by a blood clot [18] and the other one,
was occluded by normal brain tissue [17]. Bates et al., reported that half of all shunt malfunctions within the first 2
years are associated with proximal catheter blockage [27].

Browd et al., described that choroid plexus ingrowth may
obstruct the proximal catheter and surgical removal is
complicated due to the risk of bleeding by the avulsion of the
choroid plexus [28]. In the first case, the G force in the roller
coaster ride could induce movement of the proximal catheter
avulsed the choroid plexus starting a coagulation process and
the blood clot occluded the proximal catheter leading to a
shunt malfunction.

In the second case, the article describes that the patient
repeated several times the ride and these could produce a
movement of the proximal catheter encrusted into the choroid
plexus causing a blockage on the proximal catheter. This case
differs from the first case in order that the obstruction was
caused by normal brain tissue and not by a clot caused by the
avulsion.

Barotrauma: Barotraumas are classified in three types:
Alternobaric, atmospheric and Inner Ear Decompression
Sickness (IEDS) [15]. The case reported by Al-khudari was
classified as an atmospheric barotrauma, which is
characterized with extremes of pressure or abrupt changes in
the middle ear pressure. In the case, the author shows that the
pressure needed to cause an atmospheric barotrauma is 25
pounds/inch and the patient was only submitted to 0.6
pounds/inch. The pressure was not enough to injure the
tympanic membrane but was enough to collapse the capillary
network of the external auditory canal triggering an
inflammatory process [15].

The macular hemorrhage was associated also with a
barotrauma, in the article is mentioned that during the roller
coaster ride, the patients experiences an increase on the
pressure on their face. This increase in the pressure is also
exerted to the eyeball. The anterior and posterior chambers of
the eyeball are pushed to the retina and choroid layer. The
pressure exerted to the choroid layer injures the capillary bed
provoking a macular hemorrhage.

Glaucoma: Chan et al., reported in 2017 that glaucoma an
etiology was not fully characterized [29]. The traumatism
caused by the acceleration of the roller coaster propitiates an
anterior dislocation of the crystalline and vitreous humor. This
way, the trabecular mesh-work got occluded and started a
pathologic process of open angle secondary glaucoma.

Pneumothorax: Pneumothorax in young patients has
described like a valve phenomenon, generally associated with
sudden pressure changes. The abruptly descents in roller
coaster makes an abruptly inside of air to the pulmonary
parenchyma, this causes an elevation of the intra-alveolar
pressure and a laceration of the visceral pleura. The air inside cannot get out from the pleural cavity and this is resulting in
an elevation of the intrathoracic pressure.

Pulmonary hemorrhage: During the “up-and-down, to-andfro”
movements in roller coaster, it produces a tensile and
shearing tissue. One of the mainly tissues damage is the
capillary endothelium causing microhemorrhages. The
principal mechanism is a transient increase pulmonary
capillary pressure. Multiple microhemorrhages its clinical seen
like acute hemoptysis.

Conclusion

Roller coaster rides have been associated different injuries
related to acceleration, G forces, rotations and turn; it is
important to consider that modern roller coasters are getting
faster and furious and can reach as high as 6 Gs, these could
increase the injuries associated to the roller coaster. To know
the risk for humans in roller coaster is necessary to know many
parameters not only G force, it is important to take into
account the Kinematic parameters of body motion, the direction (linear or rotational), duration and magnitude of
motion.

Although the risk of injury is low, emergency physicians
should know that amusement park rides could be related to
inexplicable symptoms associated with damage caused by
extreme conditions of roller coaster rides, so physicians should
stay alert when patients mention that they attend an
amusement park. Some cases presented in this review were
correlated to pre-existing trauma or aneurism [30].

It is important to mention that in some cases the patient
repeated the ride several times, like the case of macular
Hemorrhage which describes 13 rides [12], the subdural
hematoma describe at least 11 rides [19], and the acute
Parkinson syndrome after ventriculoperitoneal shunt
malfunction describe several rides [17].

A correct clinical interview must be the first step to the
correct diagnosis suspicion of this kind of injuries, Physician
should ask for visits to amusement park in the last 3 months to
the patient when there is no apparent traumatic event,
because some authors have reported that patients tend to
minimize these events and avoid them during the medical
interview [12] and other authors have reported cases where
the onset of symptoms is 2 months after the visit to the
amusement parks [20].

We try to make a correlation of the injuries with the G force
applied by the roller coaster but it was very complicated
because the articles usually do not report the G forces, we
found it only it to articles and the G forces was 4.5 and 3.5
[10,18].